Climate scientists’ worst-case scenarios back in 2007, the first year the Northwest Passage became navigable without an icebreaker (today, you can book a cruise through it), have all been overtaken by the unforeseen acceleration of events. No one imagined that twelve years later the United Nations would report that we have just twelve years left to avert global catastrophe, which would involve cutting fossil-fuel use nearly by half. Since 2007, the UN now says, we’ve done everything wrong. New coal plants built since the 2015 Paris climate agreement have already doubled the equivalent coal-energy output of Russia and Japan, and 260 more are underway.

Environmental writers today have a twofold problem. First, how to overcome readers’ resistance to ever-worsening truths, especially when climate-change denial has turned into a political credo and a highly profitable industry with its own television network (in this country, at least; state-controlled networks in autocracies elsewhere, such as Cuba, Singapore, Iran, or Russia, amount to the same thing). Second, in view of the breathless pace of new discoveries, publishing can barely keep up. Refined models continually revise earlier predictions of how quickly ice will melt, how fast and high CO2 levels and seas will rise, how much methane will be belched from thawing permafrost, how fiercely storms will blow and fires will burn, how long imperiled species can hang on, and how soon fresh water will run out (even as they try to forecast flooding from excessive rainfall). There’s a real chance that an environmental book will be obsolete by its publication date.

I’m not the only writer to wonder whether books are still an appropriate medium to convey the frightening speed of environmental upheaval. But the environment is infinitely intricate, and mere articles—much less daily newsfeeds or Twitter—can barely scratch the surface of environmental issues, let alone explore the extent of their consequences. Ecology, after all, is about how everything connects to everything else. Something so complex and crucial still requires books to attempt to explain it.

David Wallace-Wells’s The Uninhabitable Earth expands on his 2017 article of the same name in New York, where he’s deputy editor. It quickly became that magazine’s most viewed article ever. Some accused Wallace-Wells of sensationalism for focusing on the most extreme possibilities of what may come if we keep spewing carbon compounds skyward (as suggested by his title and his ominous opening line, the answer “is, I promise, worse than you think”). Whatever the article’s lurid appeal, I felt at the time of its publication that its detractors were mainly evading the message by maligning the messenger.

Two years later, those critics have largely been subdued by infernos that have laid waste to huge swaths of California; successive, monstrous hurricanes—Harvey, Irma, and Maria—that devastated Texas, Florida, and Puerto Rico in 2017; serial cyclone bombs exploding in America’s heartland; so-called thousand-year floods that recur every two years; polar ice shelves fracturing; and refugees pouring from desiccated East and North Africa and the Middle East, where temperatures have approached 130 degrees Fahrenheit, and from Central America, where alternating periods of drought and floods have now largely replaced normal rainfall.

The Uninhabitable Earth, which has become a best seller, taps into the underlying emotion of the day: fear. This book is meant to scare the hell out of us, because the alarm sounded by NASA’s Jim Hansen in his electrifying 1988 congressional testimony on how we’ve trashed the atmosphere still hasn’t sufficiently registered. “More than half of the carbon exhaled into the atmosphere by the burning of fossil fuels has been emitted in just the past three decades,” writes Wallace-Wells, “since Al Gore published his first book on climate.”

Although Wallace-Wells protests that he’s not an environmentalist, or even drawn to nature (“I’ve never gone camping, not willingly anyway”), the environment definitely has his attention now. With mournful hindsight, he explains how we were convinced that we could survive with a 2 degrees Celsius increase in average global temperatures over preindustrial levels, a figure first introduced in 1975 by William Nordhaus, a Nobel prize–winning economist at Yale, as a safe upper limit. As 2 degrees was a conveniently easy number to grasp, it became repeated so often that policy negotiators affirmed it as a target at the UN’s 2009 Copenhagen climate summit. We now know that 2 degrees would be calamitous: “Major cities in the equatorial band of the planet will become unlivable.” In the Paris Agreement of 2015, 1.5 degrees was deemed a safer limit. At 2 degrees of warming, one study estimates, 150 million more people would die from air pollution alone than they would after 1.5 degrees. (If we include other climate-driven causes, according to the Intergovernmental Panel on Climate Change, that extra half-degree would lead to hundreds of millions more deaths.) But after watching Houston drown, California burn, and chunks of Antarctica and Louisiana dissolve, it appears that “safe” is a relative statement—currently we are only at 1 degree above preindustrial temperatures.

The preindustrial level of atmospheric carbon dioxide was 280 parts per million. We are now at 410 ppm. The last time that was the case, three million years ago, seas were about 80 feet higher. A rise of 2 degrees Celsius would be around 450 ppm, but, says Wallace-Wells, we’re currently headed beyond 500 ppm. The last time that happened on Earth, seas were 130 feet higher, he writes, envisioning an eastern seaboard moved miles inland, to Interstate 95. Forget Long Island, New York City, and nearly half of New Jersey. It’s unclear how long it takes for oceans to rise in accordance with CO2 concentrations, but you wouldn’t want to find out the hard way.

Unfortunately, we’re set to sail through 1.5 and 2 degree increases in the next few decades and keep going. We’re presently on course for a rise of somewhere between 3 and 4 degrees Celsius, possibly more—our current trajectory, the UN warns, could even reach an 8 degree increase by this century’s end. At that level, anyone still in the tropics “would not be able to move around outside without dying,” Wallace-Wells writes.

The Uninhabitable Earth might be best taken a chapter at a time; it’s almost too painful to absorb otherwise. But pain is Wallace-Wells’s strategy, as is his agonizing repetition of how unprecedented these changes are, and how deadly. “The facts are hysterical,” he says, as he piles on more examples.

Just before the 2016 elections, a respected biologist at an environmental NGO told me she actually considered voting for Trump. “The way I see it,” she said, “it’s either four more years on life support with Hillary, or letting this maniac tear the house down. Maybe then we can pick up the pieces and finally start rebuilding.” Like many other scientists Wallace-Wells cites, she has known for decades how bad things are, and seen how little the Clinton-Gore and Obama-Biden administrations did about it—even in consultation with Obama’s prescient science adviser, physicist John Holdren, who first wrote about rising atmospheric CO2 in 1969. For the politicians, it was always, foremost, about the economy.

Unfortunately, as Wallace-Wells notes:

The entire history of swift economic growth, which began somewhat suddenly in the eighteenth century, is not the result of innovation or trade or the dynamics of free trade, but simply our discovery of fossil fuels and all their raw power.

This is our daily denial, which now flies in our faces on hurricane winds, or drops as hot ashes from our immolated forests and homes: growth is how we measure economic health, and growth must be literally fueled. Other than nuclear energy, which has its own problems, no form of energy is so concentrated, and none so cheap or portable, as carbon. By exhuming hundreds of millions of years’ worth of buried organic matter and burning it in a couple of centuries, we built our dazzling modern civilization, not noticing that its wastes were amassing overhead. Now we’re finally paying attention, because hell is starting to rain down.

I encourage people to read this book. Wallace-Wells has maniacally absorbed masses of detail and scoured all the articles most readers couldn’t finish or tried to forget, or skipped because they just couldn’t take yet another bummer. Wallace-Wells has been faulted for not offering solutions—but really, what could he say? We now burn 80 percent more coal than we did in 2000, even though solar energy costs have fallen 80 percent in that period. His dismaying conclusion is that “solar isn’t eating away at fossil fuel use…it’s just buttressing it. To the market, this is growth; to human civilization, it is almost suicide.”

He allows that through carbon-capture or geoengineering “or other now-unfathomable innovations, we may conjure new solutions,” but at best, he says, these will “bring the planet closer to a state we would today regard as merely grim, rather than apocalyptic.” Having read for years about geoengineering plans to reflect sunlight back into space by sending up planes to seed the stratosphere with sulfates, and to enhance the reflectivity of clouds by spraying salt to brighten them, and about machines that can suck carbon dioxide from the atmosphere, I know of some who might challenge that—but so far, none of these ideas has reached even a pilot level, let alone commercialization scale.

Current carbon-capture prototypes filter CO2 from a polluter’s exhaust so that it can be converted back into more carbon-based fuel. But this would require building enough machines to cleanse the entire atmosphere of emissions from every company and cookfire, and then burying all that captured CO2 so it can never escape—a huge and dubious undertaking. Likewise, a program to deflect solar radiation by spraying particles—as Mt. Pinatubo’s eruption did in 1991, slightly cooling the climate for two years before its dust settled back to Earth—would have to continue in perpetuity to work. Such a program would alter planetary rainfall patterns in unpredictable ways and do nothing to curb ocean acidification. Imagine getting all the world’s nations to agree to tinker with the atmosphere if it meant some of them might end up even drier than before. Several major environmental organizations that once opposed such schemes are now willing to discuss them (the goals of the Paris Agreement depend on yet-uninvented mass-scale technologies to remove atmospheric carbon), underscoring Wallace-Wells’s argument that the situation is dire indeed.

His book gives other examples of why technology probably can’t get us out of the mess that technology caused in the first place. That includes one of the biggest innovations of the twentieth century: the Green Revolution, which more than doubled grain harvests in the 1960s by selective crossbreeding of wheat, corn, and rice to get extra kernels per stalk. Wallace-Wells notes that Norman Borlaug, the agronomist behind these advances, is credited with saving a billion lives by staving off the famines that eighteenth-century demographic economist Thomas Malthus and Paul Ehrlich, author of The Population Bomb, had both predicted would inevitably result from population growth. But Borlaug never claimed to have eliminated the possibility of more famine. Upon accepting his Nobel Peace Prize in 1970, he warned that without population controls, enhanced food production would paradoxically lead to even more hunger, because people spared by famine would give birth to more people who would continually need more food.

For the rest of his life Borlaug campaigned, in vain, for universal family planning. His efforts were especially undermined when in 1984, at the International Conference on Population in Mexico City, Ronald Reagan instituted the “Global Gag Rule,” prohibiting US funding assistance for any aid program, American or foreign, that mentioned abortion as a family planning option—a rule that every Republican president since has supported. As Borlaug feared, his high-yield cereals, along with the invention of artificial nitrogen fertilizer a few decades earlier, combined to quadruple the global population during the twentieth century—a growth unprecedented in biological history for any large species. As a result, nearly half the unfrozen Earth is now devoted to growing or grazing food for humans, while other species dwindle or just disappear. Food production, reports Wallace-Wells, is also responsible for at least one third of all greenhouse gas emissions (some estimates are as high as one half when all aspects of food consumption—including shipping, refrigeration, and agrochemical costs—are considered).

“One hopes these population booms,” writes Wallace-Wells, referring to Africa, where numbers are expected to quadruple in this century, “will bring their own Borlaugs, ideally many of them.” By suggesting that overpopulation might statistically enhance the chances of producing a savior to cure us of the woes that overpopulation causes, I assume that Wallace-Wells is either being wry or simply despairing over another enormous blow that humanity is about to deliver to the planet.

The Uninhabitable Earth makes only scant reference to the holocaust that climate change is wreaking on biodiversity. (One million species are now at risk of extinction, the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services reported recently.) But Wallace-Wells’s impulse to focus on our own selfish stake in unfolding events probably makes sense—this future is real, and it’s ours. As desperate as we are to know what to do next, enlightening us about that isn’t his objective: getting our attention is.

If his book doesn’t offer a solution, Wallace-Wells does give a reason to try to find one. While he was writing the book, he and his wife had a baby daughter. The question of whether to have children in this overheating world has been tormenting many couples lately—until, on learning they’re expecting, they know the answer. A baby is not just their adored offspring: it embodies hope for the future, and parents will do anything to ensure their child has one.

P. Ravikumar/Reuters

Residents filling containers with water from a municipal tanker in Chennai, India, where parts of the city have been without running water for months, June 2019

So how do we go on? That has been Bill McKibben’s abiding concern ever since the publication in 1989 of The End of Nature, a book so well known that people who’ve never read it regularly refer to it. Its premise is that since humans altered the entire atmosphere, which touches everything on Earth, there is no truly pristine nature left. His latest book, Falter—much like his 2010 book, Eaarth, but nearly a decade deeper into the maw—begins with a clear-eyed, detailed assessment of what we’re now up against. McKibben describes just how much trouble we’re in, yet his voice is so calm, his examples so fresh and unexpected (the book begins with a meditation on roofing, of all things), that you easily glide into his lucid, engaging contemplation of the potential end of human civilization. Later in Falter, when he describes just as equably what we must do to prevent it, you believe it’s still worth trying.

I’d long admired the clarity of McKibben’s journalism. At some point, however, he apparently concluded that when a global existential crisis is bearing down, journalism can only go so far, and he became an activist. With his students at Middlebury, he cofounded 350.org, a grassroots advocacy group that has become a worldwide movement and whose name derives from the safe concentration of atmospheric CO2 in parts per million. We last saw 350 ppm thirty years ago, when The End of Nature was published. In Falter, he admits frankly to fearing that our “game, in fact, may be starting to play itself out.” Until he got too busy traveling for 350.org, McKibben, a lifelong Christian, taught Sunday school. Given all he knows, his faith surely helps keep him going. Occasionally, it appears in his writing, such as The Comforting Whirlwind, his 2005 reflection on the Book of Job’s enduring relevance. Believer and activist though he may be, McKibben doesn’t preach, and still uses the tools of journalism to investigate, illustrate, and verify.

In a chapter that begins “Oh, it could get very bad,” he discusses a study in the Bulletin of Mathematical Biology concluding that by 2100 the oceans may be too hot for phytoplankton to photosynthesize. (Another study I’ve seen, in Nature, suggests that since 1950 phytoplankton populations worldwide may have decreased by up to 40 percent, correlating to rising sea-surface temperatures.) Just as we fail to realize how much extra CO2 is in the air because it’s invisible, it’s hard to grasp how immense—and immensely bad—this news is. Tiny phytoplankton float in the ocean practically unnoticed, yet they constitute half the organic matter on Earth and provide, as McKibben notes, “two-thirds of the earth’s oxygen.” Their loss, he quotes the study’s author, “would likely result in the mass mortality of animals and humans.”

And that’s just the effects from heat. Absorption of CO2 has already made the ocean 30 percent more acidic, with pH expected to decline “well beyond what fish and other marine organisms can tolerate” by the end of this century, he writes, citing another paper. According to the Intergovernmental Panel on Climate Change, current acidification rates of seas and lakes already may be the highest in 300 million years.

McKibben shares some other harrowing examples of threatened fauna, from insects to lions, but although it’s been understood since Noah’s time that we need other species, readers best relate to our own, so like Wallace-Wells McKibben soon circles back to humans. Major cities like Cape Town and São Paulo (and several in India and China) have come within mere days of running out of water; it’s just a matter of time until one does. Outdoor work and maintenance will be halted more frequently as urban thermometers exceed 120 degrees Fahrenheit. Grain harvests will drop as temperatures rise. Insurance companies will go bankrupt after successive biblical storms destroy trillions of dollars of property. Refugees running everywhere. This won’t stop.

Even McKibben struggles for an adequate vocabulary to describe the duplicity of oil companies: “There should be a word for when you commit treason against an entire planet.” As early as 1977, one of Exxon’s own scientists explained to the company’s executives that their products were causing a greenhouse effect, and that there would be only “five to ten years before the need for hard decisions regarding changes in energy strategies might become critical.” By 1982, McKibben writes, “the company’s scientists concluded that heading off global warming would ‘require major reductions in fossil fuel combustion’” or risk “potentially catastrophic events.” Exxon used predictions of ice retreat to lengthen their drilling season in the Arctic, and raised drilling platforms to accommodate sea-level rise. He recounts the deliberate strategy of oil executives and their pet politicians to, as one Exxon official put it, “emphasize the uncertainty” of climate science. “I’ve lived the last thirty years inside that lie,” McKibben realizes, “engaged in an endless debate over whether global warming was ‘real’—a debate in which both sides knew the answer from the beginning.”

He gives the most succinct explanation I’ve ever read of how the Koch brothers and their ilk triumphed. Another character who emerges in this section, and haunts the rest of the book, is Ayn Rand. McKibben’s description of her backstory and the outsized scope of her influence on so many of today’s politicians will shock some readers into taking their tattered copies of The Fountainhead to the nearest hazardous waste disposal.

Equally cogent, and creepy, is his survey of the race for technological mastery over our natural limitations (including death) by engineering human babies using the gene-editing technology CRISPR, melding our minds with artificial intelligence and with hardware more resilient than our shambling bodies, or simply letting robots handle the hard stuff. Every day some trending new gizmo or beguiling advance distracts us from the climate disaster by promising to make our lives easier, even as our future grows shorter.

The last part of McKibben’s book is titled “An Outside Chance.” He admits that he’s not sure we have one. He argues that neither artificial intelligence nor genetic engineering will improve our odds for survival, and then he gets to Falter’s final, main point: “Let’s assume we’re capable of acting together to do remarkable things.”

This is where McKibben’s spirituality infuses his clear intellect to show how we can, and why we must. Despite his detailed and documented outrage over the wreckage caused by an “unbelievably small percentage of people at the top of the energy heap,” he—along with most humans, he maintains—still believes in humanity. He then describes two “technologies” that could be deployed to begin to reverse the damage.

The first is the simple photovoltaic solar panel. Wallace-Wells contends that, while hanging solar panels on our homes might make us feel better, we’re kidding ourselves that it makes any meaningful dent in the continued growth of the fossil fuel industry. But McKibben argues that solar energy is already undermining that industry’s expansion plans in Africa and elsewhere in the developing world. Coal and natural gas plants require complex, costly grids to deliver their energy, and customers who can afford to pay for them. McKibben visits colorful, unlikely places from rural Ghana to Ivory Coast where people with inexpensive solar cells are lighting villages, running hospitals, starting businesses, and marketing and manufacturing products—all without drilling or building networks involving power poles and miles of copper wiring. Likewise, the ubiquity of cell phones has eliminated the need to string expensive telephone lines. The next time you step outside, McKibben is urging, look at all the wires tethering us to an energy sector that’s killing us. If Africa can dispense with them, why can’t we? By 2050, according to data he cites, solar alone could provide two-thirds of the US’s energy—with the rest coming from wind turbines and hydroelectric dams—and create thirty-six million jobs.

McKibben’s second technology is what he calls “one of the signal inventions of our time”: nonviolent protest and resistance. He tells how, on its very first try, 350.org’s utterly quixotic strategy to “organize the world” ignited rallies in 181 countries in 2009. Inspired by Gandhi—McKibben is a Gandhi Peace Award laureate—and the Sermon on the Mount, he makes a surprisingly persuasive case for why the movement to stop using carbon-based fuels will ultimately win.

But whether it wins in time, he acknowledges, is another matter. As America’s ongoing racial strife shows, a half-century after Martin Luther King Jr., nonviolence doesn’t bring change overnight. Could anything reverse civilization’s suicidal course faster? Once, a well-known journalist whom I won’t name remarked, as we commiserated over the infuriating, deteriorating state of affairs we were covering, “You know that someday we’ll ditch this journalism crap and become terrorists.” I knew the feeling, but given the choice, I’ll opt for McKibben’s nonviolent activism.

It’s not only our planet that’s strained and needs saving, he concludes, but ourselves. From our plateauing height and lifespans to athletic records that haven’t been broken for years, human capacity may have finally peaked, and actually be declining. Recent data he cites show that IQs, after rising for more than a century, are now dropping. “Our task now,” as McKibben paraphrases the authors of that study, “should be to somehow maintain the gains of the past.”

In our lives and in our world, says McKibben, “There’s a time and a place for growth, and a time and a place for maturity, for balance, for scale. And the risks we’re currently running…suggest that that time is now…. Our goals need to fundamentally shift: toward repair, toward security, toward protection.” The overarching goal, he adds, is to ensure the survival of our species. “Perhaps our job, at this particular point in time, is to slow things down, just as basketball teams do when they’re ahead. If we don’t screw up the game of being human, it could last for a very long time; compared to other species, we’re still early in our career.”

Put that way, it would be a damn shame if we went extinct prematurely. With Falter, he’s offering us a game plan.